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IP-based Dynamic VLAN

There is a requirement to segregate network activity on our local campus. Currently, DHCP is used to assign IP addresses based on Vendor and User class information. Is there a way to use the assigned IP address instead of the MAC address to define VLAN membership?


Re: IP-based Dynamic VLAN

As far as I know, I don't think it's impossible. Let me explain.

The following assumes you configured a 1:1 IP subnet to VLAN scheme. With Dynamic VLAN Membership protocol the source address of the first frame (maybe even be a DHCP request) is used to determine VLAN. Once VLAN is determined, it’s assigned by the switch. The broadcast DHCP frame will be heard by the router interface residing on that VLAN. The router performs its DHCP relay function and forwards a unicast request with the requesting host subnet (VLAN) to the DHCP server. Based on this information the DHCP server knows what IP scope/subnet (VLAN) to use.

Without the subnet/VLAN already determined the DHCP process wouldn’t work in this scenario.

Can you please elaborate your requirements? Would statically configure VLANs to fulfill your requirements?

Re: IP-based Dynamic VLAN

how about using 802.1x-based vlan assignment. With these you can at least define or group the users together to be assigned to the same vlan.

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